> For the complete documentation index, see [llms.txt](https://rangle-io.gitbook.io/react-training/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://rangle-io.gitbook.io/react-training/master/lessons/redux-logging.md).

# redux-logging

## What is Redux Middleware?

* Similar to middleware in other libraries or frameworks
* Adds a way for 3rd parties to introduce their own logic or processing
* Runs between an action being dispatched and when it hits the reducer

## Logging Middleware

* Since all state updates happen through Redux actions, we have a centralized point to intercept and log state changes
* All actions having a serializable type gives us a human readable name to understand the intent of state changes
* Pure reducers make logging the before state and after state very useful and simple